Valve



Jan. 4, 1944. P. .1. MCANDREWS ,VALVE Original Filed Dec. 5, 1941 INVENTOR w E R D M C M. L k W. firm.

ATTORNEYS Patented Jan. 4, 1944 VALVE Peter J. Mclndrews, Jamaica, N. Y.

Originalapplication December 3, 1941. Serial No.

1942, Serial No. 444,698

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 2 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to an improved poppet valve, and more particularly to a poppet valve for use in connection with prime movers such as shown in my copending application Serial No. 421,476, filed December 3, 1941, of which this application is a division.

It is the object of my invention to provide a balanced poppet valve which is suitable for use either as an inlet valve or as an exhaust valve.

Other objects and advantages of my invention will become apparent upon a consideration of the following detailed description and the accompanying drawing, in which the figure is a crosssectional view of an embodiment of my invention.

A portion I of a prime mover such as illustrated in my copending application above referred to is provided in which a recess 2 is formed, said recess 2 including a reduced portion 3 at its inner end, an enlarged cylindrical portion 4, forming a shoulder 5 and an enlarged threaded portion 6 at its outer end forming a shoulder B. A passage 1 is formed in the portion I of the prime mover, which passage I leads from within the reduced portion 3 of the recess to without the portion I. A passage 29 leading into the recess 2 is also formed in the portion I of the prime mover.

A poppet valve assembly indicated generally by A is mounted within the recess 2 and comprises a head 8 of a valve, the stem 9 of which has a suitable shouldered portion It and a threaded portion II having a piston 26 threaded thereon and held against the shouldered portion II} by a lock nut 25. The valve acts in a cylinder cage I2 which is of a smaller diameter than the diameter of the cylindrical portion l of the recess 2 whereby a steam space I2 is formed around it. The cylinder cage I2 includes an inlet steam port IS on one side thereof, an outlet steam port It on its other side adjacent to its inner end, which outlet steam port I I registerswith the passage I in the portion I of the prime mover, a flange Iii which abuts against the shoulder 5 of the recess 2 and a valve seat I6 of an opening I6. The exhaust end of the cylinder cage I2 is closed by a cylindrical head I'l fitted into the reduced portion 3 of the recess 2. The opposite end of the cylinder cage I2 is threaded to fit into the inner end of a spring holder It which is formed to have a landing shoulder I9 abutting against the shoulder 6' in the recess 2. The spring holder It also includes a threaded portion threaded on the enlarged III Divided and this application May 27,

portion 5 of the recess 2 and a well 21 formed in its outer end for a purpose which will hereinafter appear, said threaded portion 20 of the spring holder I8 acting as a plug nut. The piston 26 has a steam tight fit against the inner wall of the cylinder cage I2 and is adapted for movement within the cylinder cage.

The outer end of the valve stern 9 extends through and is movab-ly mounted on the spring holder I8 and is surrounded by retracting springs 2| which extend into the well 21 at one end. The retracting springs 2I abut against the spring holder Id at their inner ends and are compressed by a spring cup 22 set over the valve stem 9 and held in place by means of a horseshoe washer 23 placed in recessed grooves 24 in the valve stem. The valve is operated by a cam rod 28 arranged to actuate the stem 9.

The operation of my improved valve is as follows:

Assuming the valve to be in its closed position as illustrated, steam under pressure entering through the passage 29 in the portion I of the prime mover, enters the space I2 around the cylinder cage I2 and then passes through the inlet port I3, where it enters the cylinder cage and, as the steam pressure builds up, pressure in the cylinder cage I2 will increase. Since the piston 26 offers a greater area to the steam than the valve head 8, the valve will tend to move in conjunction with the compressed springs 2| and firmly seat the valve. At the proper moment, the cam rod '29 lifts the valve from its seat I6 which allows the steam to pass from inlet port I3 around the valve head 8 through the valve opening I6 and out of the exhaust port I4. Since the piston 26 forms a steam tight fitting against the inner wall of cylinder cage I2, no stufiing box will be required where the valve stem 9 passes through the spring holder I8. The shoulders I5 and I9 of the valve assembly are so placed that they properly aline the inlet and exhaust ports I3 and [4, respectively, when the unit is installed in the coacting steam recess 2 1n the portion I of the prime mover by means of the plug nut 20.

While I have described my invention with particularity, it is to be understood that I do not wish to be limited to the details disclosed since various modifications within the spirit of the invention will suggest themselves to those skilled in the art.

Having described my invention, what I claim as new and wish to secure by Letters Patent is:

1. A valve comprising a cylinder and a valve member movably mounted in said cylinder, said cylinder including a valve opening and having a spring holder mounted on one end thereof, an intake port in said cylinder adjacent to and spaced from one side of the valve opening and an exhaust port in the cylinder on another side and spaced from the valve opening, said valve member movably mounted in said cylinder and comprising a head engaging the valve opening adjacent to the exhaust port, a valve stem extending from said head through the spring holder, retracting springs surrounding said valve stem and engaging the spring holder, a member holding the retracting springs under compression, said springs adapted to normally hold the valve head in contact with said valve opening, a piston fixedly mounted on and movable with said valve stem, said piston positioned Within said cylinder between said intake port and spring holder, and means for actuating said valve stem to actuate the piston in the cylinder and the valve head from the valve opening against the action of said retracting springs.

2. A valve assembly adapted to be installed in a recess formed in a prime mover having an exhaust passage formed therein extending from a said recess, said recess including an enlarged threaded portion and said valve assembly comprising a cylinder and a valve member movably mounted in said cylinder, said cylinder including a valve seat and having a spring holder mounted on one end thereof, said spring holder being in threaded engagement with the enlarged portion of said recess, an intake port in said cylinder adjacent to and spaced from one side of the valve seat and an exhaust port in the cylinder on another side and spaced from the valve seat, said exhaust port registering with said passage extending from the recess, said valve member comprising a head movably engaging the valve seat adjacent to the exhaust port, a valve stem extending from said head and movably mounted on and extending through said spring holder,

retracting springs surrounding said valve stem and engaging the spring holder, a member holding the retracting springs under compression, said springs adapted to normally hold the valve head in contact with the valve seat, a piston fixedly mounted on and movable with said valve stem within said cylinder, and means for actuating said valve stem to actuate the piston in the cylinder and the valve head from the valve seat against the action of said retracting springs.

PETER J. MCANDREWS. 

